Android - set a value of TextView to a custom TextView

Question

I have a custom textview class with this code:

    public CustomTextView extends TextView {

        public CustomTextView(Context c, AttributeSet a) {
            super(c, a);
            TextView tv = (TextView) findViewById(R.id.myTv);
            String str = tv.getText().toString();

            setText(str);
        }
    }

And my main.xml contains this:

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/myTv"
        android:text="Unkown" />

    <com.test.CustomTextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="100.0sp" />

What I want to do is I want to get the string value of the TextView(with ID of myTv) and set the text of my CustomTextView same as the TextView. Something like TextView = CustomTextView.

The string value of myTv is changed by a sharedpreferences so everytime the text changes, the custom text also will change.

My problem is how to do this correctly?

Set an ID on your custom view and update it every time your dataset changes? Almost identical to how you update your textview. If you want a text listener, check out the Android [TextWatcher](https://developer.android.com/reference/android/text/TextWatcher.html) class. — MeetTitan, Jun 14 '16 at 16:17
Yes that is possible but what I want is I will just leave the activity where the textview is. I want the custom textview to do the job and change itself everytime the textview is changed. — Jorn Blaedel Cabrera Garbosa, Jun 14 '16 at 16:21
Look into the link at the end of my comment and behold that I hath read thine mind. `yourTextView.addTextChangedListener(new TextWatcher() {...});` — MeetTitan, Jun 14 '16 at 16:29
What if the text view is plain text and not changeable, is my code correct or incomplete? — Jorn Blaedel Cabrera Garbosa, Jun 14 '16 at 16:37
Well then you go with option A of my original comment. Give it an ID and update your custom view every time you feed text to your text view. — MeetTitan, Jun 14 '16 at 16:39
Where I have to do this? In the activty or is it possible inside the custom textview class? — Jorn Blaedel Cabrera Garbosa, Jun 14 '16 at 16:44
Thanks. I figured it out now. I will just use the same sharedpreference of the textview and the custom. — Jorn Blaedel Cabrera Garbosa, Jun 14 '16 at 16:51

score 0 · Answer 1 · edited May 23 '17 at 10:29

0

This is really simple you just initialize both textviews and get string from one and set it in another. Extending your class with TextView gives you all methods TextView can use.

CustomTextView customtv = (CustomTextView) findViewById(R.id.customTv);
TextView tv = (TextView) findViewById(R.id.myTv);
customtv.setText(tv.getText());

Just set id on your CustomTextView whatever you want i used customTv id in this case.

EDIT:

As far as i understood you want textChangeListener, here is example.

edited May 23 '17 at 10:29

Community

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answered Jun 14 '16 at 16:22

Ivan Marincic

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2
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Sorry I didnt understand your answer. What I want is I dont want to edit the activity where textview is and let the customtextview change itself. – Jorn Blaedel Cabrera Garbosa Jun 14 '16 at 16:26
How do you mean change itself. Do you mean everytime you update textview your customtextview changes too or... – Ivan Marincic Jun 14 '16 at 16:27
My main goal is I just want the custom textview to be just the same value of the text view. – Jorn Blaedel Cabrera Garbosa Jun 14 '16 at 16:39
Im sorry im not good in english so I cant really explain clearly. – Jorn Blaedel Cabrera Garbosa Jun 14 '16 at 16:40
I can see what are you talking about. But you are making things overly complicated can't you just make same logic for updating both textviews – Ivan Marincic Jun 14 '16 at 16:45

Android - set a value of TextView to a custom TextView

1 Answers1